Oscillatory actuator



Dec. 27, 1960 R. E. SELF 2,966,144

oscILLAToRY ACTUATOR wwg n@ ORNEYS Dec 27, 19,60 R. E. SELF 2,966,144

OSCILLATORY ACTUATOR Filed July 15, 1958 2 Sheets-Sheet 2 ',2 @ya /Z Y INV ENTOR vRhara EMS'eIf BY t v ,JM 9M @2f/@wf M 2,966,144 ICC Patented Dec. 2'?, i960 oscILLAToRY AcTUAToR Richard E. Self, Sherman Oaks, Calif., assignor to C. L. Norsworthy, Jr., Dallas County, Tex.

Filed July 15, 1958, Ser. No. 748,702

3 Claims. (Cl. 121-99) This invention relates to devices for translating the power of fluid under pressure into oscillatory mechanical motion or vice versa and particularly to oscillatory actuators and other power devices of the pressure uid actuator type including hydraulic and pneumatic devices such as are utilized in aircraft, missiles, and other machinery in the form of actuators, pumps, dampeners, and the like.

The general object of this invention is to provide an improved uid sealing arrangement for preventing the escape or by-passing of fluid from or between the fluid pressure chambers of such devices.

More particularly, the invention relates to an oscillatory actuator wherein a rotor has one or more radially and axially extending vanes projecting from a generally cylindrical hub or shaft, and a pair of circular end members to which the axial extremities of said vanes are united. This rotor is mounted for oscillation in a generally cylindrical housing having one or more inwardly projecting gates extending radially and axially of the rotor between the circular end members so that the vanes, gates, circular end members, hub, and inner walls of the housing together form two or more iluid pressure chambers, the relative volumes of which vary as the rotor oscillates.

The principal object of the invention is to provide an improved sealing means, having a minimum number of leak paths, for sealing such a rotor to such a housing. The invention contemplates an arrangement of mutually cooperating sealing elements carried by the rotor and by the housing for sealing the peripheries of the several lluid pressure chambers within the device in such a manner as to reduce the number of leak paths from the sixteen found in most conventional oscillatory actuators to a minimum of four leak paths for a dual vane-quadruple pressure chamber actuator.

To attain this result in a dual vane-quadruple pressure chamber actuator, the invention of this application utilizes a pair of endless seals mounted in the outer surface of the rotor and extending in arched form around the respective semicircular halves of the rotor and bearing against the cylindrical inner wall of the housing with uid sealing contact; together with a pair of linear strip seals mounted in the inner surface of the respective partition gates of the housing and having end portions in crossed relation to the semicircular end portions of the rotor seals. The leak paths are thus restricted to the four points of crossing of the respective ends of the two strip seals.

lt will be apparent as the description proceeds that the principles of this invention may be applied not only to a dual vane-quadruple pressure chamber actuator but also to a single vane-dual pressure chamber actuator or to a three vane-six pressure chamber actuator or even to an actuator having a greater number of vanes and pressure chambers.

This application is a continuation-in-part of United States patent application, Serial No. 690,336, led October 15, 1957 by this same inventor. Many of the constructional details of the device of that application may be embodied in the device specifically disclosed here. The invention of the present application is an improvement over the invention of the earlier application in that it provides for a greater angle of rotation of the rotor for a given number of vanes and pressure chambers. This is the result of the use of the linear strip seals mounted in the inner surface of the partition gates as contrasted to having all of the seals mounted in the rotor as was the case in the earlier application.

The appended drawings and the following detailed description of the embodiment of the device shown in those drawings will reveal other objects and advantages of this invention. It is to be understood that the embodiment here illustrated and described is simply illustrative of the principles of this invention and a showing of the best arrangement presently known. Neither the drawings nor the following description should be considered as limiting the scope of the invention to what is specifically shown and described.

In the drawings,

Figure l is a cross sectional View of a dual vanequadruple pressure chamber actuator constructed in accordance with the principles of this invention, the View being taken at right angles to the axis and approximately midway of the length of the device; y

Figure 2 is a sectional view of the same device taken along the axis and on the lines 2 2 of Figure l;

Figure 3 is a fragmentary sectional view of a modified device, this View being taken along the axis in a manner similar to that of Figure 2, but showing the part of the rotor which it includes in full and not in section;

Figure 4 is a fragmentary sectional View taken along lines 4-4 of Figure 3;

Figure 5 is a sectional View taken along lines 5-5 of Figure l, but showing the rotor only partially cut away; and

Figure 6 is a perspective view of the rotor shown in the preceding figures.

As illustrated in Figures 1, 2, 5 and 6, the preferred form of the device of this invention is a dual vanequadruple pressure chamber actuator, the principal elements of which consist of a housing iii in which an oscillating rotor 11 is mounted. As illustrated, the housing 1@ consists of a generally cylindrical portion 12, the ends of which are closed by end plates i3 in which the rotor is journaled for oscillation. The end plates 13 are held in place by snap rings 14 which snap into grooves l5 in the cylindrical member 12 and leakage between the end plates and the cylindrical portion is prevented by an O-ring 15 mounted in a peripherally extending groove in each end plate 13.

At each end of the rotor 11 an axially extending shaft 17 is provided and this shaft is journaled in a corresponding opening in the corresponding end plate i3. An O-ring 18 journaled in a groove in each of the shafts 17 prevents leakage between the shaft and its corresponding end plate. One or both of the shafts 17 extends from the device and is connected by means not shown to whatever mechanism the device is to operate.

Immediately inside of the end plates 13, the rotor 11 expands to form generally conically shaped elements 20 which are clearly visible in Figures 2 and 6, and these conical shaped elements are joined together by an axially extending cylindrical shaped element 21. A pair of vanes 22 and 23 extend both axially and radially of the rotor between the end cones 20 and from the cylindrical or hub portion 21 outwardly to a radius equal to the largest radius of the conical portions 20.

The inside of the housing 12 is generally cylindrical so as to receive the rotor `11 and permit it to oscillate therein, but the housing does have a pair of inwardly extending gate members 25 and 26 as seen in Figures 1 numeral 51.

and 2, which gate members are shaped to extend inwardly towards the axis of the device and longitudinally along the axis of the device so as to contact or substantially contact the hub or cylindrical portion 21 of lthe rotor and the sloping surfaces of the conical elements 29. Thus, as shown in Figure l, four pressure chambers are provided 30, 31, 32 and 33. An inlet 34 is provided to pres-V sure chamber 33 and an inlet 35 to pressure chamber 32. The pressure chamber 33 is connected so the pressure can flow from it to pressure chamber 31 by a diagonally extending opening 36 through the rotor and pressure from the chamber 32 is carried to the chamber 30 by a similar diagonally extending opening 37.

In order to provide eiiicient sealing between the various pressure chambers, a pair of continuous seals 38 and 39 are provided and mounted in the rotor as shown particularly in Figure 6. Thus, the seal 3S extends along the outer face of one of the vanes 23 of the rotor in a groove provided therein to receive it, thence half way rOund the periphery of one of the end portions 20 of the rotor, again in a groove provided to receive it, thence back across the outer face of the other vane 22 again in a groove provided to receive it, and finally half way around the periphery of the other end portion 2G of the rotor to the starting point. The second continuous seal 39 parallelsthe rst seal across the outer edge of the vane 23, then around the other half of the conical member 20 on the right-hand end of the rotor as seen in Figure 6, then parallels the rst mentioned sealing means along the outer edge of the vane 22 and then around the other half of the cylindrical element shown on the left-hand of Figure 6 and back to its starting point.

The result of the use of the two continuousiseals thus far described is to thoroughly and completely isolate the pressure spaces 30 and 31 Vfrom the pressure spaces 32 and 33, but these seals do not act to separate the pressure space 30 from pressure space 31 or pressure space 32 from pressure space 33, as will appear from an inspection of Figure l.

In order to seal the pressure space 30 from pressure space 31, and the pressure space 32 from the pressure space 33, another seal is provided which seal is mounted not in the rotor but in the housing and more particularly in the gates 25 and 26 of the housing. As illustrated in Figures l and 2, this sealing means consists of a sealing strip 40 mounted in a groove 41 in the cylindrical housing 12 and particularly in its gate portion 25, and another similar sealing strip Vi3 similarly mounted in a groove in the housing and the gate member 26. As i1- lustrated in Figures l and 2, a -round strip of resilient material 45 is placed under each of the sealing strips 40 and 43 to press it against the hub portion of the rotor and effect a tight seal. As can also be seen in Figure 2, the sealing strips @il and 43 extend longitudinally to the ends of the inside of the housing and thus, pass under and in contact with the continuous sealing members 38 and 39 which are mounted Vin the rotor. This occurs in four places in the device and these are the only four places where there is any tendency for leakage to occur. However, since there are only four such places and even these places are small and well protected against leakage, the leakage in the device is reduced to minimum.

As can be seen in Figures 3 and 4, a slightly diierent construction has been used in that a marcel spring has been used instead of a round resilient material to back the sealing elements which are mounted in the cylindrical housing. In these figures, the sealing elements are indicated by the numeral 50 and the marcel spring by the The continuous sealingmembers 38 and 39 that are mounted in the surface of the 'rotor are preferably'of cir,- cular cross section and of a yieldable resilient'material 'such as a s'o-ft synthetic elastomer, soft rubber, or other similar material. Neoprene is the Vdu Pont trademark for Yi4fhlerebuteeliene, .1.3. which falls is the elessleetee of soft synthetic elastomers useful for this purpose. Other chloloprene rubbers may be used.

The sealing strips 40 and 43 which are mounted in the housing can also be made of a soft sealing material but preferably are of a harder more wear resistant type of sealing material such as, for example, a tetrafluoroethylene polymer, which du Pont sells under lthe trademark Teon. The loading strips which push this material against the rotor are preferably of a soft rubber or the like. As previously pointed out, however, the sealing strips mayY be pressed against the rotor by a marcel spring or other equivalent means instead of by a resilient strip.

What is claimed is:

1. In anoscillatory actuator, in combination: a rotor including a cylindrical hub, a pair of diametrically opposed radial vanes and a pair of concentric circular heads at respective ends of the hub, to which the ends of said vanes and of said hub are integrally joined; a housing in which said rotor is rotatably mounted, said housing including a lateral wall member having diametrically epposed reenfrant gates and .segmental Cylindrical wel! portions bridging between said gates, said housing further including full-eyligdrieal end portions projecting eX- ially beyond the ends of said gates, said gates each including a central portion adjacent said hub and portions at each end of said central portion and extending divergently axially outwardly to Said fully cylindrical end portions, said rotor heads being rotatably fitted within said housing end portions; a pair of endless seals of cylindrically warped rectangular ring form each including a pair of semi circular end portions mounted in the peripheries of the respective rotor heads, and a pair of straight lateral portions disposed in the longitudinal .outer margins of said vanes and joined to said semi circular end portions by corner portions disposed at the junctions between said vane outer margins and said head periphcries, the said semi circular portions of the respective seals being in abutting relation at said corner portions to cooperatively define full-circular `sectional seal rings in each rotor head periphery, in sealing contact'with the inner walls of said full-cylindrical end portions of the Y housing, and said lateral portions of the respective seals on each side of the rotor being disposed along-side one another and in contact with the inner walls of said segmental-cylindrical housing portions; and linear seals seated in the respective gates', each said linear seal disposed in median radial planes thereof and including a straight central portion extending longitudinally in the inner longitudinal extremity of its respective gate, a pair of in,- termediate portions diverging outwardly along and in the respective end walls of its respective gate, and a pair of end portions extending axially outwardly in the cylindrical inner walls of the respective housing end portions and in crossing contact with the respective semi-cylindrical portions of-said endless seal.

2. In an oscillatory actuator, in combination: a rotor including a cylindrical hub, a pair of vanes projecting radially therefrom in diametrically opposed relation, and a pair of circular heads at respective ends of the hub, to which the ends of said vanes and said hub are integrally joined, said heads having frusto-conical internal walls converging inwardly from their peripheries to the ends of said hub, said vanes having longitudinal marginal faces extending between and at the same diameter as the peripheral faces of Ysaid heads, said peripheral faces havins Circular ring Seat grooves therein and Said marginal faces having axially extending lateral ring seat grooves bridging between and communicating with and twice as wide as said circular ring seat grooves; a housing in which said rotor is rotatably mounted, said housing including a generally cylindrical open-ended lateral wall member having diametrically opposed `reentrant gates and Sesniemelaylindfeel rertienebridsins between ,n SE

gates, said housing further including full cylindrical end portions projecting axially beyond the ends of said gates and receiving said rotor heads, said gates being of trape- Zoidal sectional contour in a radial plane, having straight inner margins and end walls diverging outwardly from the ends thereof to said full-cylindrical housing end portions, and having a pair of linear seal grooves disposed respectively in the median axial planes or said gates and each including a straight portion in the inner extremity of a respective gate, a pair of intermediate portions in the ends of the respective gate, and a pair of end portions in the respective cylindrical end portions of the housing; a pair of endless seals each including a pair of sernicircular end portions mounted in the respective circular grooves and a pair of straight lateral portions disposed in the respective lateral grooves, the said seni-circular portions of the respective seals cooperatively deiining full circular sectional seal rings in each end of the rotor, projecting from said circular grooves into sealing contact with the inner walls oi said ful-cylindrical end portions or" the housing, and said lateral portions of the respective seals at each side of the rotor being disposed alongside of and in contact with one another within said lateral grooves and projecting therefrom into contact with the inner walls of said segmental-cylindrical housing portions; and linear seals disposed in the respective linear seal grooves and following the contour of the respective gates in said axial planes, each of said linear seals including respective end portions disposed in the said end portions of said linear seal grooves and in crossed sealing contact with respective semi-circular end portions of a respective endless seal.

3. In an oscillatory actuator, in combination: a rotor including a cylindrical hub, a pair of diametrically opposed radial vanes and a pair of concentric circular heads at respective ends of the hub, to which the ends of said vanes and of said hub are integrally joined; a housing in which said rotor is rotatably mounted, said housing including a lateral wall member having diametrically opposed reentrant gates and segmental cylindrical wall portions bridging between said gates, said housing further including full-cylindrical end portions projecting beyond the ends of said gates, said rotor heads being rotatably fitted within said housing end portions; a pair of endless seals of cylindrically warped rectangular ring form each including a pair of sernieircular end portions mounted in the peripheries or the respective rotor heads, and a pair of straight lateral portions disposed in the longi tudinal outer margins of said gates and joined to said semicircular end portions by corner portions disposed at the junctions between sm'd gate outer margins and said head peripheries, the said semicircular portions of the respective seals being in abutting relation at said corner portions to cooperatively deiine full-circular sectional seal rings in each roto-r head periphery, in sealing contact with the inner walls of said full-cylindrical end portions of the housing, and said lateral portions of the respective seals and each side of the rotor being disposed alongside one another and in contact with the inner walls of said segmental-cylindrical housing portions; and linear seals seated in the `respective gates, disposed in median radial planes thereof and each including the straight central portion extending longitudinally in the inner longitudinal extremity of a respective gate, a pair of intermediate portions diverging outwardly along and in the respective end walls of a respective gate, and a pair of end portions extending axially outwardly in the cylindrical inner walls of the respective housing end portions and in crossing contact with the respective semicylindrical portions of a respective endless seal, said rotor heads having frusto-conical internal faces extending from their peripheries to the respective ends of said hub and in mutually aring relation corresponding to the divergence of said intermediate portions of the linear seals, and including yielding loading strips interposed between the respective linear seals and the bottoms of the respective linear seal grooves and resiliently pressing said linear seals into contact with the surface of said hub, said truste-conical faces of the heads, and the peripheries of said heads respectively.

References Cited in the tile of this patent UNITED STATES PATENTS 540,492 Humes June 4, 1895 2,540,903 Moushey et al. Feb. 6, 1951 FOREIGN PATENTS 623,229 Great Britain May 13, 1949 

